Ever since I saw this video, I've been wanting to cook fish sous vide in my kitchen sink, but until recently I've been too busy for cooking experiments. This past Sunday, though, we decided to finally make tilapia in the sink. I'll also note this is a really kid-friendly method of cooking, since (until the last step) the temperatures involved are pretty low, and kids can help by holding the thermometer, or by dropping the bagged fish into the sink.
First, we filled the sink with hot tap water, at a temperature which is good for this sort of fish:
Then, we bagged the filets with a little bit of olive oil, and immersed in cold to squeeze out the air (in retrospect, I probably could have done this step right in the sink). Then, they went for a swim in the water for around 15 minutes (look up tables of cooking times in a book, or just calculate it yourself). Since we were eating these right away, we didn't need to worry about pasteurization issues.
To finish, I seared them in a pan with butter and capers (which became all crispy), topped with fresh ground green pepper and a squeeze of lemon, and served them with quinoa. They didn't need added salt; the capers were sufficient:
This actually turned out to be a really quick and easy way of cooking the fish to a perfect doneness in a nearly-foolproof way. It has the added benefit of not heating up my kitchen on a hot summer day. I am definitely going to be doing this more!